AstraZeneca, Waltham, Massachusetts
When AstraZeneca extended its administration and research facilities in Waltham, Massachusetts, ventilation systems were required for both the administrative buildings and the research and development laboratories.
From chilled beams to comfort modules
AstraZeneca had previous experience of chilled beams. It was now interested in four-way air distribution, a technology that was not widely used in the USA at that time. Four-way offered the potential to reduce costs by having fewer beams, achieve a higher cooling output from more compact ceiling-mounted units, and also include some of the facility’s laboratory areas.
Incoming air is filtered three times before entering the buildings. A central cooling system supplies all the buildings with water at a temperature between 11°C and 15°C (according to the season). A temperature-controlled mixing station on the top floor of each building keeps the water in a supply loop slightly above 15°C, making condensate drainage in the cooling flows unnecessary.
Supplied primary air is cooled and mixed with the recirculated air flows before entering the loop sections. The primary air pressurises the office spaces above the connecting laboratories and is transferred via grills above the ceiling and into the laboratories like incoming air, which achieves further energy savings.